* Use 1-byte-read instead of -write for iprobe() function
  Add i2c commands to PM826 config

* extend I2C POST code: check for list on known addresses
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
new file mode 100644
index 0000000..5bf75ac
--- /dev/null
+++ b/tools/env/fw_env.c
@@ -0,0 +1,662 @@
+/*
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <linux/mtd/mtd.h>
+#include "fw_env.h"
+
+typedef	unsigned char	uchar;
+
+#define	CMD_GETENV	"fw_printenv"
+#define	CMD_SETENV	"fw_setenv"
+
+typedef struct envdev_s {
+	uchar devname[16]; /* Device name */
+	ulong env_size;    /* environment size */
+	ulong erase_size;  /* device erase size */
+} envdev_t;
+
+static envdev_t envdevices[2];
+static int curdev;
+
+#define DEVNAME(i)    envdevices[(i)].devname
+#define ENVSIZE(i)    envdevices[(i)].env_size
+#define DEVESIZE(i)   envdevices[(i)].erase_size
+
+#define CFG_ENV_SIZE ENVSIZE(curdev)
+
+#ifdef HAVE_REDUND
+#define ENV_SIZE (CFG_ENV_SIZE - sizeof(long) - 1)
+#else
+#define ENV_SIZE (CFG_ENV_SIZE - sizeof(long))
+#endif
+
+typedef struct environment_s {
+	ulong	crc;		/* CRC32 over data bytes	*/
+	uchar   flags;      /* active or obsolete */
+	uchar *data;
+} env_t;
+
+static env_t environment;
+static int valid = 0;
+
+#ifdef HAVE_REDUND
+static uchar active_flag = 1;
+static uchar obsolete_flag = 0;
+#endif
+
+#define XMK_STR(x)	#x
+#define MK_STR(x)	XMK_STR(x)
+
+static uchar default_environment[] = {
+#ifdef	CONFIG_BOOTARGS
+	"bootargs="	CONFIG_BOOTARGS			"\0"
+#endif
+#ifdef	CONFIG_BOOTCOMMAND
+	"bootcmd="	CONFIG_BOOTCOMMAND		"\0"
+#endif
+#if (CONFIG_BOOTDELAY >= 0)
+	"bootdelay="	MK_STR(CONFIG_BOOTDELAY)	"\0"
+#endif
+#if (CONFIG_BAUDRATE >= 0)
+	"baudrate="	MK_STR(CONFIG_BAUDRATE)		"\0"
+#endif
+#ifdef	CONFIG_ETHADDR
+	"ethaddr="	MK_STR(CONFIG_ETHADDR)		"\0"
+#endif
+#ifdef	CONFIG_IPADDR
+	"ipaddr="	MK_STR(CONFIG_IPADDR)		"\0"
+#endif
+#ifdef	CONFIG_SERVERIP
+	"serverip="	MK_STR(CONFIG_SERVERIP)		"\0"
+#endif
+	"\0"
+};
+
+static int  flash_io (int mode);
+static uchar *envmatch(uchar *s1, uchar *s2);
+static int env_init(void);
+static int parse_config(void);
+
+
+/*
+ * Search the environment for a variable.
+ * Return the value, if found, or NULL, if not found.
+ */
+unsigned char *fw_getenv (unsigned char *name)
+{
+	uchar *env, *nxt;
+
+	if (env_init())
+		return (NULL);
+
+	for (env=environment.data; *env; env=nxt+1) {
+		uchar *val;
+
+		for (nxt=env; *nxt; ++nxt) {
+			if (nxt >= &environment.data[ENV_SIZE]) {
+				fprintf (stderr, "## Error: "
+					"environment not terminated\n");
+				return (NULL);
+			}
+		}
+		val=envmatch(name, env);
+		if (!val)
+			continue;
+		return (val);
+	}
+	return (NULL);
+}
+
+/*
+ * Print the current definition of one, or more, or all
+ * environment variables
+ */
+void fw_printenv(int argc, char *argv[])
+{
+	uchar *env, *nxt;
+	int i, n_flag;
+
+	if (env_init())
+		return;
+
+	if (argc == 1) {		/* Print all env variables	*/
+		for (env=environment.data; *env; env=nxt+1) {
+			for (nxt=env; *nxt; ++nxt) {
+				if (nxt >= &environment.data[ENV_SIZE]) {
+					fprintf (stderr, "## Error: "
+						"environment not terminated\n");
+					return;
+				}
+			}
+
+			printf("%s\n", env);
+		}
+		return;
+	}
+
+	if (strcmp(argv[1], "-n") == 0) {
+		n_flag = 1;
+		++argv;
+		--argc;
+		if (argc != 2) {
+			fprintf (stderr, "## Error: "
+				"`-n' option requires exactly one argument\n");
+			return;
+		}
+	} else {
+		n_flag = 0;
+	}
+
+	for (i=1; i<argc; ++i) {	/* print single env variables	*/
+		uchar *name = argv[i];
+		uchar *val = NULL;
+
+		for (env=environment.data; *env; env=nxt+1) {
+
+			for (nxt=env; *nxt; ++nxt) {
+				if (nxt >= &environment.data[ENV_SIZE]) {
+					fprintf (stderr, "## Error: "
+						"environment not terminated\n");
+					return;
+				}
+			}
+			val=envmatch(name, env);
+			if (val) {
+				if (!n_flag) {
+					fputs (name, stdout);
+					putc  ('=',  stdout);
+				}
+				puts  (val);
+				break;
+			}
+		}
+		if (!val)
+			fprintf (stderr, "## Error: \"%s\" not defined\n",
+			 name);
+	}
+}
+
+/*
+ * Deletes or sets environment variables. Returns errno style error codes:
+ * 0	  - OK
+ * EINVAL - need at least 1 argument
+ * EROFS  - certain variables ("ethaddr", "serial#") cannot be
+ *	    modified or deleted
+ *
+ */
+int fw_setenv (int argc, char *argv[])
+{
+	int  i, len;
+	uchar *env, *nxt;
+	uchar *oldval = NULL;
+	uchar *name;
+
+	if (argc < 2) {
+		return (EINVAL);
+	}
+
+	if (env_init())
+		return (errno);
+
+	name = argv[1];
+
+	/*
+	 * search if variable with this name already exists
+	 */
+	for (env=environment.data; *env; env=nxt+1) {
+		for (nxt=env; *nxt; ++nxt) {
+			if (nxt >= &environment.data[ENV_SIZE]) {
+				fprintf (stderr, "## Error: "
+					"environment not terminated\n");
+				return (EINVAL);
+			}
+		}
+		if ((oldval=envmatch(name, env)) != NULL)
+			break;
+	}
+
+	/*
+	 * Delete any existing definition
+	 */
+	if (oldval) {
+		/*
+		 * Ethernet Address and serial# can be set only once
+		 */
+		if ((strcmp (name, "ethaddr") == 0) ||
+		    (strcmp (name, "serial#") == 0) ) {
+			fprintf (stderr, "Can't overwrite \"%s\"\n", name);
+			return (EROFS);
+		}
+
+		if (*++nxt == '\0') {
+			*env = '\0';
+		} else {
+			for (;;) {
+				*env = *nxt++;
+				if ((*env == '\0') && (*nxt == '\0'))
+					break;
+				++env;
+			}
+		}
+		*++env = '\0';
+	}
+
+	/* Delete only ? */
+	if (argc < 3)
+		goto WRITE_FLASH;
+
+	/*
+	 * Append new definition at the end
+	 */
+	for (env=environment.data; *env || *(env+1); ++env)
+		;
+	if (env > environment.data)
+		++env;
+	/*
+	 * Overflow when:
+	 * "name" + "=" + "val" +"\0\0"  > CFG_ENV_SIZE - (env-environment)
+	 */
+	len = strlen(name) + 2;
+	/* add '=' for first arg, ' ' for all others */
+	for (i=2; i<argc; ++i) {
+		len += strlen(argv[i]) + 1;
+	}
+	if (len > (&environment.data[ENV_SIZE]-env)) {
+		fprintf (stderr,
+			"Error: environment overflow, \"%s\" deleted\n",
+			name);
+		return (-1);
+	}
+	while ((*env = *name++) != '\0')
+		env++;
+	for (i=2; i<argc; ++i) {
+		uchar *val = argv[i];
+
+		*env = (i==2) ? '=' : ' ';
+		while ((*++env = *val++) != '\0')
+			;
+	}
+
+	/* end is marked with double '\0' */
+	*++env = '\0';
+
+WRITE_FLASH:
+
+	/* Update CRC */
+	environment.crc = crc32(0, environment.data, ENV_SIZE);
+
+	/* write environment back to flash */
+	if (flash_io (O_RDWR)) {
+		fprintf (stderr,
+			"Error: can't write fw_env to flash\n");
+		return (-1);
+	}
+
+	return (0);
+}
+
+static int flash_io (int mode)
+{
+	int fd, fdr, rc, otherdev, len, resid;
+	erase_info_t erase;
+	char *data;
+
+	if ((fd = open(DEVNAME(curdev), mode)) < 0) {
+		fprintf (stderr, 
+				 "Can't open %s: %s\n", 
+				 DEVNAME(curdev), strerror(errno));
+		return (-1);
+	}
+
+	len = sizeof(environment.crc) + sizeof(environment.flags);
+
+	if (mode == O_RDWR) {
+#ifdef HAVE_REDUND
+		/* switch to next partition for writing */
+		otherdev = !curdev;
+		if ((fdr = open(DEVNAME(otherdev), mode)) < 0) {
+			fprintf (stderr, 
+					 "Can't open %s: %s\n", 
+					 DEVNAME(otherdev), strerror(errno));
+			return (-1);
+		}
+#else
+		otherdev = curdev;
+		fdr = fd;
+		len = sizeof(environment.crc);
+#endif
+		printf("Unlocking flash...\n");
+		erase.length = DEVESIZE(otherdev);
+		erase.start = 0;
+		ioctl (fdr, MEMUNLOCK, &erase);
+
+#ifdef HAVE_REDUND
+		erase.length = DEVESIZE(curdev);
+		erase.start = 0;
+		ioctl (fd, MEMUNLOCK, &erase);
+		environment.flags = active_flag;
+#endif
+		printf("Done\n");
+		resid = DEVESIZE(otherdev) - CFG_ENV_SIZE;
+		if (resid) {
+			if ((data = malloc(resid)) == NULL) {
+				fprintf(stderr, 
+				  "Cannot malloc %d bytes: %s\n",
+				  resid, strerror(errno));
+				return (-1);
+			}
+			if (lseek (fdr, CFG_ENV_SIZE, SEEK_SET) == -1) {
+				fprintf (stderr,
+				  "seek error on %s: %s\n", 
+				   DEVNAME(curdev), strerror(errno));
+				return (-1);
+			}
+			if ((rc = read (fdr, data, resid)) != resid) {
+				fprintf (stderr,
+				  "read error on %s: %s\n", 
+				  DEVNAME(curdev), strerror(errno));
+				return (-1);
+			}
+			if (lseek (fdr, 0, SEEK_SET) == -1) {
+				fprintf (stderr,
+				  "seek error on %s: %s\n", 
+				  DEVNAME(curdev), strerror(errno));
+				return (-1);
+			}
+		}
+
+		printf("Erasing old environment...\n");
+
+		erase.length = DEVESIZE(otherdev);
+		if (ioctl (fdr, MEMERASE, &erase) != 0) {
+			fprintf (stderr, "MTD erase error on %s: %s\n",
+			  DEVNAME(otherdev), strerror(errno));
+			return (-1);
+		}
+
+		printf("Done\n");
+
+		printf("Writing environment to %s...\n",DEVNAME(otherdev));
+		if (write(fdr, &environment, len) != len) {
+			fprintf (stderr,
+			  "CRC write error on %s: %s\n", 
+			  DEVNAME(otherdev), strerror(errno));
+			return (-1);
+		}
+		if (write(fdr, environment.data, ENV_SIZE) != ENV_SIZE) {
+			fprintf (stderr,
+			  "Write error on %s: %s\n", 
+			  DEVNAME(otherdev), strerror(errno));
+			return (-1);
+		}
+		if (resid) {
+			if (write (fdr, data, resid) != resid) {
+				fprintf (stderr,
+				 "write error on %s: %s\n", 
+				  DEVNAME(curdev), strerror(errno));
+				return (-1);
+			}
+			free(data);
+		}
+#ifdef HAVE_REDUND
+		/* change flag on current active env partition */
+		if (lseek (fd, sizeof(ulong), SEEK_SET) == -1) {
+			fprintf (stderr,
+			  "seek error on %s: %s\n", 
+			  DEVNAME(curdev), strerror(errno));
+			return (-1);
+		}
+		if (write (fd, &obsolete_flag, sizeof(obsolete_flag)) != 
+			sizeof(obsolete_flag)) {
+			fprintf (stderr,
+			 "Write error on %s: %s\n", 
+			 DEVNAME(curdev), strerror(errno));
+			return (-1);
+		}
+#endif
+		printf("Done\n");
+		printf("Locking ...\n");
+		erase.length = DEVESIZE(otherdev);
+		erase.start = 0;
+		ioctl (fdr, MEMLOCK, &erase);
+#ifdef HAVE_REDUND
+		erase.length = DEVESIZE(curdev);
+		erase.start = 0;
+		ioctl (fd, MEMLOCK, &erase);
+		if (close(fdr)) {
+			fprintf (stderr,
+			 "I/O error on %s: %s\n", 
+			 DEVNAME(otherdev), strerror(errno));
+			return (-1);
+		}
+#endif
+		printf("Done\n");
+	} else {
+#ifndef HAVE_REDUND
+		len = sizeof(environment.crc);
+#endif
+		if (read (fd, &environment, len) != len) {
+			fprintf (stderr,
+			 "CRC read error on %s: %s\n", 
+			 DEVNAME(curdev), strerror(errno));
+			return (-1);
+		}
+		if ((rc = read (fd, environment.data, ENV_SIZE)) != ENV_SIZE) {
+			fprintf (stderr,
+			 "Read error on %s: %s\n", 
+			  DEVNAME(curdev), strerror(errno));
+			return (-1);
+		}
+	}
+
+	if (close(fd)) {
+		fprintf (stderr,
+		  "I/O error on %s: %s\n", 
+		  DEVNAME(curdev), strerror(errno));
+		return (-1);
+	}
+
+	/* everything ok */
+	return (0);
+}
+
+/*
+ * s1 is either a simple 'name', or a 'name=value' pair.
+ * s2 is a 'name=value' pair.
+ * If the names match, return the value of s2, else NULL.
+ */
+
+static uchar *
+envmatch (uchar *s1, uchar *s2)
+{
+
+	while (*s1 == *s2++)
+		if (*s1++ == '=')
+			return(s2);
+	if (*s1 == '\0' && *(s2-1) == '=')
+		return(s2);
+	return(NULL);
+}
+
+/*
+ * Prevent confusion if running from erased flash memory
+ */
+static int env_init(void)
+{
+	int crc1, crc1_ok;
+	uchar *addr1;
+#ifdef HAVE_REDUND
+	int crc2, crc2_ok;
+	uchar flag1, flag2, *addr2;
+#endif
+
+	
+	if (!valid) {
+
+		if (parse_config()) /* should fill envdevices */
+			return 1;
+
+		if ((addr1 = calloc (1, ENV_SIZE)) == NULL) {
+			fprintf (stderr, 
+			 "Not enough memory for environment (%ld bytes)\n",
+			 ENV_SIZE);
+			return (errno);
+		}
+
+		/* read environment from FLASH to local buffer */
+		environment.data = addr1;
+		curdev = 0;
+		if (flash_io (O_RDONLY)) {
+			return (errno);
+		}
+
+		crc1_ok = ((crc1 = crc32(0, environment.data, ENV_SIZE)) 
+			 == environment.crc);
+#ifndef HAVE_REDUND
+		if (!crc1_ok) {
+			fprintf (stderr, 
+			 "Warning: Bad CRC, using default environment\n");
+			environment.data = default_environment;
+			free(addr1);
+		}
+#else
+		flag1 = environment.flags;
+		
+		curdev = 1;
+		if ((addr2 = calloc (1, ENV_SIZE)) == NULL) {
+			fprintf (stderr, 
+			 "Not enough memory for environment (%ld bytes)\n",
+			 ENV_SIZE);
+			return (errno);
+		}		
+		environment.data = addr2;
+
+		if (flash_io (O_RDONLY)) {
+			return (errno);
+		}
+
+		crc2_ok = ((crc2 = crc32(0, environment.data, ENV_SIZE)) 
+				   == environment.crc);
+		flag2 = environment.flags;
+		
+		if (crc1_ok && ! crc2_ok) {
+			environment.data  = addr1;
+			environment.flags = flag1;
+			environment.crc = crc1;
+			curdev = 0;
+			free(addr2);
+		}
+		else if (! crc1_ok && crc2_ok) {
+			environment.data  = addr2;
+			environment.flags = flag2;
+			environment.crc = crc2;
+			curdev = 1;
+			free(addr1);
+		}
+		else if (! crc1_ok && ! crc2_ok) {
+			fprintf (stderr, 
+			 "Warning: Bad CRC, using default environment\n");
+			environment.data = default_environment;
+			curdev = 0;
+			free(addr2);
+			free(addr1);
+		}
+		else if (flag1 == active_flag && flag2 == obsolete_flag) {
+			environment.data  = addr1;
+			environment.flags = flag1;
+			environment.crc = crc1;
+			curdev = 0;
+			free(addr2);
+		}
+		else if (flag1 == obsolete_flag && flag2 == active_flag) {
+			environment.data  = addr2;
+			environment.flags = flag2;
+			environment.crc = crc2;
+			curdev = 1;
+			free(addr1);
+		}
+		else if (flag1 == flag2) {
+			environment.data  = addr1;
+			environment.flags = flag1;
+			environment.crc = crc1;
+			curdev = 0;
+			free(addr2);
+		}
+		else if (flag1 == 0xFF)	{
+			environment.data  = addr1;
+			environment.flags = flag1;
+			environment.crc = crc1;
+			curdev = 0;
+			free(addr2);
+		}
+		else if (flag2 == 0xFF) {
+			environment.data  = addr2;
+			environment.flags = flag2;
+			environment.crc = crc2;
+			curdev = 1;
+			free(addr1);
+		}
+#endif		
+		valid = 1;
+	}
+	return (0);
+}
+
+
+static int parse_config()
+{
+	struct stat st;
+
+	if (stat (DEVICE1_NAME, &st)) {
+		fprintf (stderr, 
+		 "Cannot access MTD device %s: %s\n", 
+		 DEVICE1_NAME, strerror(errno));
+		return 1;
+	}
+
+	strcpy(DEVNAME(0), DEVICE1_NAME);
+	ENVSIZE(0) = ENV1_SIZE;
+	DEVESIZE(0) = DEVICE1_ESIZE;
+#ifdef HAVE_REDUND
+	if (stat (DEVICE2_NAME, &st)) {
+		fprintf (stderr, 
+		 "Cannot access MTD device %s: %s\n", 
+		 DEVICE2_NAME, strerror(errno));
+		return 1;
+	}
+	strcpy(DEVNAME(1), DEVICE2_NAME);
+	ENVSIZE(1) = ENV2_SIZE;
+	DEVESIZE(1) = DEVICE2_ESIZE;
+#endif
+	return 0;
+}